Abstract: A fiber optic polarimetric strain sensor and associated data acquisition system capable of all-optical measurements of physical parameters, such as structural strain, gas and liquid pressure, acceleration and vibration, gas and liquid flow rate, and force without fire and explosion hazards associated with conventional strain gage technologies, such as resistance foil strain gages. The polarimetric strain sensor houses a sensitive element—a length of single mode optic fiber—changing polarization of a single-mode optical signal running in the fiber under some mechanical affects, specifically twisting and radial compressing. A linearly-polarized light passes the sensor, which causes polarization deviation of the light, particularly, polarization plane rotation under mentioned above twisting or compressive stresses applied to a sensitive element of the sensor.

Abstract: An optical switch for coupling a trunk optic fiber to a selected branch optic fiber is disclosed. The switch includes one or two optically active elements which are capable of being configured to have a different diffraction angle. The elements are configured so that an optical signal emitted from the trunk fiber is directed into the selected branch fiber. The switch may also operate in reverse to couple a signal from the branch fiber into the trunk fiber.

Abstract: An optical switch for coupling a trunk optic fiber to a selected branch optic fiber is disclosed. The switch includes one or two optically active elements which are capable of being configured to have a different diffraction angle. The elements are configured so that an optical signal emitted from the trunk fiber is directed into the selected branch fiber. The switch may also operate in reverse to couple a signal from the branch fiber into the trunk fiber.